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2 years ago

7. A box is pulled straight across the floor at a constant speed. It is pulled with a horizontal force of 48 N.

Physics

1 answer:

Leya [2.2K]2 years ago

4 0

Answer:

a)Taking into consideration Newton’s second law, we know that

Net_Force = mass * acceleration

Since the box is pulled at constant speed, the acceleration is equal to zero.

This means that

Net_Force = 0 N

b) Force of friction

The net force is equal to the sum of all forces,

Net_Force = Force_applied - Friction

We found that Net_Force = 0, which means

Friction = Force_applied = 48 N

c) If the box comes to a stop. And the applied force becomes zero, the friction force becomes also zero.

Friction = 0 N

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1 year ago

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A long, thin solenoid has 450 turns per meter and a radius of 1.06 . The current in the solenoid is increasing at a uniform rate

kirill115 [55]

Answer:9.34 A/s

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2 years ago

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faust18 [17]

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average mass per person = 60 kg.
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one person's worth of momentum = (m) (v) = 420 kg.m/s
sum of two billion of them = 8.4 x 10¹¹ kg-m/s all in the same direction

Earth's "recoil" momentum = 8.4 x 10¹¹ in the opposite direction = (m) (v)

Divide each side by 'm' :   v = (momentum) / (mass) =

The Earth's "recoil" velocity is (8.4 x 10¹¹) / (5.98 x 10²⁴) =

   1.405 x 10⁻¹³ m/s =

   <em> 0.00000000014 millimeter per second

</em>I have no intuitive feeling for this kind of thing, so can't judge whether
the answer is reasonable. But my math and physics felt OK on the
way to the solution, so that's my answer and I'm sticking to it.

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3 years ago